Optical and structural properties of ZnO nanostructure synthesized by thermal evaporation.

摘要

Presently, ZnO nanostructures have found an intensive interest due to its wide applications in solar cells, UV lasers, nanogenerators, light emitting diodes, piezoelectronics, gas sensors and field emission devices. In this work, ZnO nanostructure is grown and characterized by field emission scanning electron microscope (FESEM), Energy Dispersive Miscrocope (EDS), X-ray diffraction (XRD) and photoluminescence (PL). Two emission peaks at wavelength 380 nm and 521 nm have been observed which corresponds to near band edge of bulk ZnO and green emission respectively. These peaks have been attributed to the excitonic transitions occurred from valence to conduction band and electronic transitions occurred between deep level defect states due to oxygen vacancies and interstitial of zinc. XRD measurement showed the hexagonal phase of synthesized ZnO nanostructure. FESEM analysis showed that the prepared ZnO nanostructure is composed of nanorodsanowires in hexagonal shape with the diameter about 40 nm while EDS measurement has confirmed dense nanostructure with the compositional peaks of zinc and oxygen peaks.